I gotta say that researching is very difficult when it comes to measurements and characteristics of some of these traps.

1. Is the main difference between #5 & #15 the Jaws? Both have teeth but #5 jaws totally close and the #15 has the 3/4" open gap? correct or no.
2. Do the center of jaws get wider in the middle on the #15?
2a.From what I found, the Jaws on the 5 & 15 are 11 3/4" is that across or diameter when opened?
3. Are they both 29" long?
4. With the dipping process, Is it a hard kind of look like a black hard tar. Don't think it is paint. see photo below.
5. On photo below, I have seen many photos of the #5 and #15 with the cross bars fairly smooth, and this one looks really beat. Is that rust deterioration or crude forge hammering?

Really appreciate the help. I have used the search option without much success.

1. The only difference between a Newhouse #5 and #15 of the same model is that the #15 has off-set jaws.
2. Yes, it is not by much but the jaws on a #15 are wider in the center than they are to the outside.
3. Yes, a #5 and a #15 Newhouse of the same model are the same length.
4. There are different types of trap dip, some are thin and some are more tar lick but not usually heavy. In the photo, it looks like paint.
5. The base is made from flat stock and is smooth. This trap just has pitting from rust. I see you are in Florida, that is a typical look of traps near the coast and salt but fresh water will rust them also. Traps from Arizona and other desert areas are generally in better condition.

thank you. that really helps. So no doubt it is a 15. i have been looking at 15s and many are 34" long mine is 29" did they come with 2 different size springs? as far as the paint/dip, when i was looking close and it appeared to be a hard tar type coating with a bit of shine which drew my attention to it. I'm fairly experience in old paint on metal, it didn't strike me as paint.
I learned of the dip and figured that is what it was. It doesn't have any chipping but rubbing off on moving parts. looking it seems to be thicker coat than paint.
I believe it came from up north as i'm in a tourist / retirement area on florida beach and most antiques from up north gets sold off before retiring to florida. We don't see much stuff down here like this. When we were in Indiana, stuff like this were everywhere.
really appreciate the help.

We do have our share of bears here, but I can't imagine this large trap being used to trap any of them. lol. My understanding this trap came from the north. I do alot of estate sales and most of the estates down here where I'm located is from retired Northerners who came down. To keep this and bring with to retire to florida must have meant something. Most items like this would have been sold / auctioned /estate sale before officially moving down to florida. Here in the tourist / retirement area of florida beach there just isn't any real antiques like this down here as it is already sold off before moving here. When we lived in Indiana, this stuff was very common. Maybe not the rare ones, but rusty metal is my forte. lol. thanks for commenting. This trap is mean, I wouldn't want to tangle with it.

was meaning to say, our bears aren't super big. I live a block from the beach and really all we get is them walking through our yards, ripping our big plastic trash cans apart. lol. they may get bigger a bit further north. We have a forestry close by which may cause the population into neighborhoods. You hurt one in any way, even if it killing your dog, you will go to jail. Even to shoot to scare it away, Jail !! That is if someone reports you. I gotta say, some of these nosey bodies here would happily call.